Re: its asking me for a serial number but i just paid for creative cloud one year prepaid

You can try this:

Creative Cloud applications ask for serial number

If that does not help then:

Uninstall Adobe Creative Cloud.

For Windows:

Open the Windows Control Panel > Programs And Features.

For MAC:

Open Finder and go to /Applications/Utilities/Adobe Installers.

After Uninstall navigate to the OOBE folder.

Windows: C Drive\Users\[user name]\AppData\Local\Adobe\OOBE

Mac OS: /Users/[user name]/Library/Application Support/Adobe/OOBE

Delete OOBE folder.

Download Creative Cloud Reinstall and Sign in .

https://creative.adobe.com/products/creative-cloud

Help articles:

Access hidden user library files | Mac OS 10.7 and later